Never mind Kurtley Beale's impression of a novice on ice at the end of the first Test, that match was decided in the first minute, not the last, when Christian Leali'ifano knocked himself out. The centre this week showed with his nerveless goal-kicking in another oscillating, tense encounter that was effectively his international debut. If Brisbane was all about the injuries the Wallabies suffered, the second Test turned when a Lion was helped from the field.

There have been times in recent weeks and months when Sam Warburton's worth has been questioned but as long as he was on the field the Lions dictated. Even Mark Ella, Australia's entertainer in the 1980s, was salivating at the thought of a Wallaby back division containing three playmakers in an era when they have not always had one but they found making plays nigh impossible when Warburton was on the field, operating behind the gainline and panicking under pressure.

Warburton would make a tackle, get back on his feet instantly, contest the ball if a turnover was on but more often he would get back out in the defensive line and wait for the next ball-carrier. It was such a non-stop, physically gruelling effort that it was perhaps a surprise that his hamstring and other bits of his body lasted as long as 67 minutes.

Australia had been behind for most of the game and even Will Genia, the tormentor in Brisbane, was struggling to find a way out of the maze, a quiet desperation creeping into his game: He not only had Warburton to contend with but a fly-half in James O'Connor who thinks like the wing he is, considering his own options before looking outside.

When Warburton went off, Genia began to dictate. He brought Israel Folau more into play and as Australia started to get over the gainline, they achieved the width that had eluded them for most of the match. The Lions became stretched and there were nine minutes to go when they achieved position in the opposition 22 for the first time in the game. They were 15-9 down and at the stage when they needed to score a try to sustain their ambition of winning the series.

That prospect had looked distant until Warburton's departure. He and his international colleague Dan Lydiate had helped contain Genia, and the Wallabies for the most part had allowed the Lions to isolate ball-carriers, contest the breakdown and win a penalty if not the ball. On the occasions when Australia fashioned some space, they suffered from a plague of unforced errors, an egregious series of knock-ons a consequence of the occasion rather than the conditions that could not have been more conducive to running rugby with the roof closed and the playing surface dry.

The Lions had chosen a bench that would give them the impetus in the final quarter they lacked last week, when a comfortable lead found itself at the mercy of Beale's boot, but they faded again. Their game had been based on defence, the prerogative of a side one-up in the series but it meant they never had a lead that was worth more than a converted try. They were, after an adventurous opening, like a team in football who have secured a score draw in a European tie and set out in the home leg not to concede.

The Lions had started boldly, kicking a penalty to touch after Halfpenny had hit the bar and, shades of Wales against New Zealand last November, brought backs into the lineout and subsequent maul, a 12-man surge towards the line that was halted by a collapse.

The referee, Craig Joubert, whose interpretations at the scrum and breakdown were so markedly different to Chris Pollock's in the first Test that the bulk of the breakdown penalties this time went to the Lions.

Ben Youngs, who was uncomfortable in the Lions restrictive gameplan, wasted an advantage by losing the ball. It was the only time the Lions set up camp in Australia's 22. Their tactic for the most part was not to run the ball in their own territory and play the game within range of Halfpenny's boot but Youngs's box-kicking tended to be under or overdone – and it was a questionable tactic anyway given the proficiency of Australia's back three under the high ball.

When the Lions did play through the fly-half Jonathan Sexton, he surprised defenders but there was never a sequence of play when the ball went through the hands of the backs.

The centres, Jonathan Davies and Brian O'Driscoll, were starved for long periods and their decision-making suffered, the latter especially: rarely has the Irishman been so erratic with the ball in hand; the wings were little more than kick-chasers – George North was initially shown up by Folau but achieved a measure of retribution when he took his opposite number for a ride on his back – and the 420 metres Australia ran with the ball on the night compared with the Lions' 148.

The tactic, though, was working until Warburton's injury. Australia led 6-3 after 23 minutes through two Leali'ifano penalties, both given against Mako Vunipola for collapsing but rarely in recent years has an attacking team been penalised so regularly at the breakdown: when Ben Mowen was blown after releasing the tackler, getting back on his feet and contesting for the ball only to be shoved by an opponent, it summed up the swing from the previous week.

The Lions were not complaining this time because Halfpenny's fourth penalty gave them a 12-9 lead at the interval. That became 15-9 with 17 minutes to go after an Australia scrum ended in a heap: Warren Gatland had kept Vunipola on, which may have been reward for the prop's work in the loose or a reflection of a distinct lack of confidence in the bench loosehead Ryan Grant, effectively the fifth choice this tour.

It was not enough of a lead. Genia's scheming took Australia within striking distance and, after taking a scrum instead of a penalty, a series of forays took them with five metres of the line. Vunipola's tackle on Genia looked to have halted the danger but the scrum-half looked right, passed left and Adam Ashley-Cooper stepped inside Davies.

Leali'ifano's angled conversion gave the Wallabies the lead but the twist had only just started its spiral. O'Connor committed a wretched error from the restart by kicking the ball dead on the full; Richard Hibbard's throw to Tom Croft was snaffled by Liam Gill and there were four seconds left when Joubert pinged Australia for holding on.

Two drives later, Mowen was caught on the wrong side and Halfpenny, like Beale the week before, had a chance to win the game. He tried to steal a few metres but was spotted by the referee and while he did not fall over, his kick fell short and, as in 1989 and 2001, it will be decided in Sydney.